The stock C4 wiring to the fuel pump is adequate for stock power. Once you start turning up the wick though, every last ounce of power needs to get to your fuel pump to ensure you've got the power to supply the motor with enough fuel at full boost.
This kit makes that as easy as possible. The relay and fuse holder get installed just behind the battery, then a pre-terminated harness routes behind the seat to the tank access panel. The stock pins get pulled out of the connector and the new pins on the 034 harness with heavy gauge wire get inserted into the stock connector.
Then with a single but-splice connection (heat shrink splice providede with kit) to the original fuel pump power, your new relay system is up and running. Kit include full install instructions and diagrams. There is no simpler option out there!